A collection of one or more computers and their associated software is commonly called a computer infrastructure. Each computer in the computer infrastructure is generally operable to communicate with each other computer in the infrastructure. Computer infrastructures having a service oriented architecture (“SOA”) are increasingly being developed. A computer infrastructure having a SOA has core functions that are partitioned into a plurality of loosely coupled functional core services. Such functional core services, which are hereinafter referred to as services, are representations of one or more functions performed by the SOA computer infrastructure. For example, one service in a SOA computer infrastructure may perform a printing function, while another service may perform a file storage function.
A service may be executed on one or more computer of a SOA computer infrastructure in accordance with computer readable instructions embodied in software or firmware. For example, a service may be embodied in Java computer code and executed on a single computer of a SOA computer infrastructure. As another example, a service may be embodied in C++ computer code that is executed in a distributed manner on three computers of a SOA computer infrastructure.
A SOA computer infrastructure generally includes a message-oriented middleware (“MOM”) application that implements messaging services within the infrastructure. The messaging services allow elements of the SOA computer infrastructure, such as services, to exchange information by exchanging messages between destinations. An example of a MOM application is a Java Messaging Service (“JMS”).
A message may include information such as data, requests, commands, and/or instructions. A message may also include message identification and routing information, commonly collectively referred to as a header. For example, a header may include a “reply-to” field that specifies where a response to the message should be delivered.
As stated above, messages are generally exchanged between destinations. A destination is a logical point or construct that serves as a relay point during a message exchange; the destination provides a logical place for two or more elements (e.g. services) of a SOA infrastructure to exchange a message. A service may publish a message to a destination or monitor the destination for receipt of a message. For example, a first service may publish a message to the destination, and a second service may monitor the destination in order to receive the message. A given service may be operable to communicate with a plurality of destinations at a give time.
An example of SOA computer infrastructure is a order processing system that allows a user to purchase an airline ticket. The order processing system includes a plurality of computers, some of which are located in different physical locations, and a plurality of services, which perform specific functions required by the order processing system. For example, the order processing system may include a query service, which is used to query an airline's database for available flights, and a purchasing service, which is used to purchase a ticket from the airline. As additional examples, the order processing system may include a financial transaction processing service, which may be used to process a user's credit card, and an itinerary service, which may be used to generate a user's flight itinerary. Each service may be executed on one or a plurality of the order processing system computers.
SOA computer infrastructures are typically developed incrementally—the framework of the infrastructure is typically developed before the services. Individual services are then added to the framework as they become available. Even if a service is available, it may not be completely functional due to it being incomplete and/or defective.
It is problematic that SOA computer infrastructures frequently cannot be fully tested during their development due to one or more services being unavailable or not fully functional. Consequently, the service's interaction with the infrastructure and/or other services may not be tested. Unavailability or lack of functionality of a service may therefore result in increased development time, development costs, and/or development complexity of a SOA computer infrastructure. Furthermore, a service's unavailability or lack of functionality may impede demonstration of the SOA computer infrastructure to an interested party. For example, a lack of one or more services may prevent a demonstration of a SOA computer infrastructure to a prospective purchaser of the infrastructure.
Accordingly, what is needed is a service proxy that can be used to emulate one or more missing and/or not fully functional services in a computer infrastructure during its development.